Centrifugal fuel supply means for jet engine afterburners



Nov. 17, 1953 w. H. BROWN 2,659,195

CENTRIFUGAL FUEL SUPPLY MEANS FOR JET ENGINE AFTERBURNERS Filed Aug. 9, 1949 2 Sheets-Sheet l FIG.2

INVENTOR W|'L IAM I-l. BROWN ATTORNEY ROWN SUP AFTE W. H. B

Nov. 17, 1953 2 Sheets-Sheet 2 PLY MEANS FOR RBURNERS CENTRIF'UGA F JET ENGI Filed Aug. 9, 1949 INVE WILLIAM BY W W ATTORNEY m. :111 1. 4 l x Mw/s NTOIR H. BROWN Patented Nov. 17, 1953 CENTRIFUGAL FUEL SUPPLY MEANS FOR' JET ENGINE AFTERBURNERS William H. Brown, Manchester, Conn., assignor to United Aircraft Corporation, East Hartford, Conn., a corporation of Delaware Application August 9, 1949, Serial No. 109,283

1 Claim.

This invention relates to an arrangement for the distribution of fuel to the afterburner in a compressor-turbine type of power plant.

The horsepower or thrust of a jet engine of either the turbo-jet or turbo-prop type may be increased by burning fuel in the gas exhausting from the turbine before it is discharged through the thrust nozzle, such burning of fuel being referred to as afterburning. A feature of the present invention is an arrangement for distributing fuel in the exhaust gas to insur complete burning of the fuel and substantially uniform heating of the exhaust gas by the fuel.

Another feature is an introduction of the fuel into the annular stream of exhaust gas from the turbine by means of a spinning ring mounted on the turbine. One feature is th arrangement of the ring such that the distribution of fuel across the annular stream of gas will be substantially uniform.

Other objects and advantages will be apparent from the specification and claim and from the accompanying drawings which illustrate an embodiment of the invention.

Fig. 1 is a sectional view through a gas turbine power plant showing the afterburner.

Fig. 2 is a sectional view on a larger scale showing the turbine with the fuel ring mounted thereon.

Fig. 3 is a view similar to Fig, 2 showing a modification.

With reference first to Fig. 1, the power plant has an inlet 2 to a compressor 4 which has a plurality of rows of stationary vanes 6 cooperating with rows of blades 8 on the rotor l0. Gas from the compressor is discharged into one or more combustion chambers l2 arranged in a ring around the shaft l4 that connects the compressor rotor ID to the turbine rotor l6. Fuel is admitted to the combustion chamber or chambers by a number of fuel nozzles l8.

The heated gas from the combustion chambers is directed through a turbine 20 having rows of nozzle vanes 22 cooperating with rows of blades 24 on the rotor l6. Gas from the turbine is discharged through an annulus 26 between a duct 28 and a tail cone 3!] and through a thrust nozzle 32. It will be understood that the power plant shown is only one of several arrangements of the type of power plants for which the afterburner arrangement, hereinafter described, is adapted.

Referring now to Fig. 2, fuel is discharged into the annular gas path 26 by means of a ring 34 mounted as by bolts 36 to the downstream side of the turbine rotor. The ring which is con-- centric with the rotor has a plurality of perfora tions 38 in its periphery through which fuel is sprayed radially outward from the ring and into the path of the gas discharging from the turbine. Fuel may be supplied to the ring through a duct 40 which may be located within one of the supporting legs 42 for the rear bearing 44 for the turbine shaft.

For the purpose of assuring a uniform distribution of fuel across the entire radial dimension of the annular gas path, the ring 34 may have the discharge openings 38 so arranged that some of the openings are spaced radially from the axis of rotation a greater distanc than the remainder. Thus, as shown in Fig. 2, the upstream row 38A of the perforations are located on a diameter greater than the succeeding rows 38B, the outer surface of the ring being arranged oblique to the axis of rotation for this purpose. With the perforations 38A at a larger radius from the axis of rotation, it will be apparent that the pressure head developed within the ring will be greater and the spray from this row of openings will thereby be carried a greater distance radially than the spray from the adjacent row. It will be noted that the ring 34 forms an annular trough, the inner surface of which is open so that fuel from the duct 40 and the cooperating longitudinally extending duct 46 may flow directly into the annular trough.

Provision may be made for igniting the mixture of fuel and gas downstream of the turbine, as, for example, by means of a spark plug 48 carried by the duct 28, and the duct 28 and cooperating nozzle 32 are made long enough so that complete combustion will normally occur before the gas is discharged through the nozzle.

In the modification of Fig. 3, the gas flows over a series of nozzle vanes 50 onto the turbine blades 52 on the periphery of the rotor 54 and thence into the annular space between the tail cone 5B and the outer duct wall 58. The tail cone is supported in position by radially extending supporting webs 60 through one of which the fuel duct 62 extends for delivering fuel to a stationary distributing head 64 having opening 66 in its periphery for discharging fuel into the spinning fuel ring 68 mounted as by bolts 10 on th downstream side of the turbine disc. The openings 12 in this ring are arranged in a manner similar to those above described in connection with Fig. 2 with the upstream rows of openings located at a greater radial distance from the axis of rotation than at succeeding rows. Here again, as in Fig. 2, the ring forms an annular trough open at its inner surface so that fuel in the inner opening 65 may be discharged directly into the trough.

It is to be understood that the invention is not limited to the specific embodiment herein illustrated and described, but may be used in other ways without departure from its spirit as defined by the following claim.

I claim;

In a fuel supply devic for a gas turbine power plant afterburner, the combination of a turbine including a rotor, a duct through which exhaust. gases passing through the turbine are discharged, a fuel supply ring mounted on the downstream side of the rotor and rotating saidring being coaxial with the rotor and a flange substantially frusto-conical in shape and tending to converge in a downstream direetiomtwo or more circumferential rows of holes around the flange and through which fuel may be discharged into said exhaust duct, the circumferential row of holes nearest the rotor being at the greatest radial distance from the axis of rotation of the ring with the radial distance of the remaining rows being progressively less in a downstream direction so that fuel pressur head in each cir- 2 ctrnferential rc-w due to centrifugal force is pro- 4 gressively less in a downstream direction and equal radial distribution as Well as equal circumferential distribution of fuel in the exhaust duct can be obtained.

5 WILLIAM H. BROWN.

References Cited in the fileof this patent UNITED STATES PATENTS m Number Name Date 2,360,130 Heppner Oct. 10, 1944: 2,386,911 Anxionnaz Mar. 19, 1946 2304 76? Heppner July 23, 1946 2,416,389 Heppner Feb. 25, 1947 2,479,726 Price Aug. 23, 1949 2,506,6 1 Neal May 9, 1950 2,540,991 Price Feb. 6, 1951 2,547,959 Miller Apr. 10, 1951 2,566,270 Price Aug. '7, 1951 20 2,566,373 Bedding Sept, 4, 1951 2,568,921 Kroon Sept. 25, 1951 2,570,591 Price Oct. 9, 1951 FOREIGN PATENTS 5 Number Country Date 383,966 France Jan. 23, 1908 

